BoilerFaultCodesTechnical description
Partially blocked pilot filter or pilot injector.
What causes this fault?
This fault occurs when the small pilot flame becomes too weak or unstable to heat the safety sensor. The most common cause is a buildup of microscopic dust or carbon soot that partially chokes the tiny hole in the pilot burner, preventing the boiler from safely transitioning to the main heating stage.
This issue often surfaces in autumn when a boiler is turned on for the first time after being dormant all summer, as settled dust is more likely to cause a blockage.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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